Anti-Saccharomyces cerevisiae mannan antibodies in familial Crohn's disease

Familial and sporadic inflammatory bowel disease: different entities?

The strongest risk factor for developing inflammatory bowel disease (IBD) is having a relative with the disease. Familial IBD may be one homogeneous subgroup, phenotypically different from sporadic IBD. Several observations support a role for familiarity in disease site and behavior, particularly in Crohn's disease (CD), but published findings do not all concur. Early disease onset is often found in children with IBD who have a parent with the disease. Genetic anticipation may explain this finding but other explanations and/or observational biasis are more likely. Location and type may differ between familial and sporadic CD cases: family studies report many cases involving both small bowel and colon, and few cases of colonic disease alone, although such features may be secondary to early age at onset. Most studies found no effect of positive family history on severity and course of CD. In ulcerative colitis (UC), phenotypic differences between familial and sporadic cases appear to be limited, but little data are available for analysis. No difference has been found between familial and sporadic IBD as far as disease markers such as pANCA, ASCA, or intestinal permeability are concerned. In conclusion, the only message available for clinical practice is that the relative risk of IBD in first-degree relatives is increased by a factor of 10-15 compared with the general population. Families should not receive genetic counseling/information about age at onset and disease severity.

Saccharomyces boulardii in maintenance treatment of Crohn's disease

The possible role of Saccharomyces boulardii, a nonpathogenic yeast with beneficial effects on the human intestine, in the maintenance treatment of Crohn's disease has been evaluated. Thirty-two patients with Crohn's disease in clinical remission (CDAI < 150) were randomly treated for six months with either mesalamine 1 g three times a day or mesalamine 1 g two times a day plus a preparation of Saccharomyces boulardii 1 g daily. Clinical relapses as assessed by CDAI values were observed in 37.5% of patients receiving mesalamine alone and in 6.25% of patients in the group treated with mesalamine plus the probiotic agent. Our results suggest that Saccharomyces boulardii may represent a useful tool in the maintenance treatment of Crohn's disease. However, in view of the product's cost, further controlled studies are needed to confirm these preliminary data.

Serologic testing for inflammatory bowel disease

OBJECTIVES

To determine the accuracy of anti-neutrophil cytoplasmic antibodies (ANCAs) and anti-Saccharomyces cerevisiae antibodies (ASCA) in distinguishing patients with inflammatory bowel disease from patients with other disorders, seen in a pediatric gastroenterology clinic setting, and in distinguishing ulcerative colitis (UC) from Crohn's disease (CD).

STUDY DESIGN

Serum samples from 120 children with new or established diagnoses of UC (n = 25) or CD (n = 20) and control children (n = 74) were analyzed in blinded fashion for the presence of IgG ANCAs and IgA and IgG ASCA.

RESULTS

The highest sensitivity for detecting inflammatory bowel disease, 71%, was achieved by using ANCAs and ASCA together. The best test for UC was ANCAs, which had a sensitivity of 80%. However, the ANCA pattern characteristic of UC, perinuclear ANCAs eliminated by DNAse, had a sensitivity of 60%. High-titer ANCAs were specific for UC, whereas ASCA were specific for CD.

CONCLUSIONS

Testing for ANCAs and ASCA together did not achieve sensitivity necessary for population screening. However, ANCAs and ASCA may be helpful in evaluating children suspected of having inflammatory bowel disease and in distinguishing UC from CD.